The use of printed circuit cards or boards is particularly advantageous in facilitating the rapid repair of malfunctioning electronic devices which include such circuit cards. The equipment may quickly be returned to service without removal from the operating site merely by unplugging and removing the printed circuit cards, one at a time, and substituting for the removed card a like printed circuit card known to be properly functional. After each substitution is made, the equipment is tested to see if that particular substitution has resulted in repair of the device. Thus, the faulty printed circuit card may quickly and easily be isolated and the same thereafter returned to a testing laboratory or facility for repair. Accordingly, the technician in the field requires only minimal skills for the removal and substitution of printed circuit cards and as such need have little or no knowledge of the actual electronics within the equipment. This frees individuals having valuable technical skills from equipment troubleshooting in the field so as to enable them to more effectively utilize their time for circuit development and the like.
As a consequence, it is particularly advantageous to maintain a large supply of spare, properly functional printed circuit cards at locations where such cards are in constant use, such as telephone switching stations and the like. It is likewise often important to maintain a supply of printed circuit cards for performing alternative functions different from those normally performed by the operating equipment, as in a telephone office where a customer desiring additional features on his phone line may be accommodated merely by the substitution of a printed circuit card having the additional capabilities for the one formerly provided on the line without time-consuming and expensive rewiring.
Devices for storing printed circuit cards are well known in the art. Various storage devices have been developed which include adjustable card receiving spaces to accommodate circuit cards having varying heights. For example, U.S. Pat. Nos. 4,184,599 and 4,277,220 disclose printed circuit card storage devices which are adjustable to accommodate a variety of card heights. Printed circuit cards are generally very delicate components and proper storage requires that the cards be securely held in place but not subjected to undue pressure which may warp or otherwise damage the card. The proper adjustment of card receiving space in the above listed patents can be difficult and time consuming since no device is provided for aiding the fine adjustment of the card receiving space to ensure that the card is properly secured.
U.S. Pat. No. 5,168,431 describes a height adjusting mechanism for a circuit card storage device which permits for fine adjustment of the card receiving space. However, the mechanism involves several moving parts and is therefore, unduly complicated and occupies a considerable amount of vertical space which would ideally be used for storing cards.
Accordingly, it would be desirable to provide an adjustable circuit card storage device having a printed circuit card receiving space which can be easily, finely adjusted to properly secure the cards within.